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Don’t like sea level rise projections? Make them illegal

North Carolina has come up with an unexpected new method of
dealing with climate change: legislating sea levels lower.

Fed up with scientists threatening the future of the state's
property developments with tiresomely high projections of sea level
rise, the state senate has just passed a bill that would forbid
taking estimates of accelerating sea level rise into account when
planning new coastal developments.

Sea level is a bit of a preoccupation in North Carolina because
the state is low-lying, flat and has an extensive coastline. You
might think this would lead local policymakers to argue for better
flood protection or even efforts to address carbon emissions, but
apparently not so.

The people behind the bill clearly understand the risks sea level
rise poses. Senator David Rouzer explained the devastation a
39-inch (about a metre)rise predicted by a group of local
scientists would cause to the local economy:

"How's that going to affect property
values? And because of the effect on property values, that's going
to affect tax revenues for those coastal counties. It's going to
affect Insurance rates and everything else."

Bill HB 819 would require North Carolina's Coastal Resources
Commission - which controls planning along the coast - to base its
future predictions of sea level rise on those made by NC-20, a
group representing coastal development companies, businesses and
local people which predicts sea level rise of just eight inches (20
centimetres) by 2100, by basing calculations on previous linear
trends and discounting the possibility that sea level rise could be
accelerating.

So why are scientists so intent on ruining coastal development
plans?

Gloomy scientists

The Science
Panel on Coastal Hazards, appointed by the North Carolina
Department of Environment and Natural Resources, concluded from a
review of research that policy and development planners should
prepare for a sea level rise of one metre by 2100.

This projection is based on the idea that as the planet warms
global sea level rise will accelerate, as the world's ice melts
faster - known as a 'semi-empirical' approach. The method is not
without its critics, but projections that don't consider this
accelerating relationship are
thought to underestimate future sea level rise, so are assumed
to provide only a lower bound on future sea level rise.

Another scientist's work appears to bear out the panel's
conclusions. Professor Ben Horton,
University of Pennsylvania and his team analysed sediment cores
from coastal marshes in North Carolina containing layers of
microfossils that contain information on past sea level change. He
told us that his team's
research shows:

"[T]he rate of sea-level rise on the
U.S. Atlantic coast is greater now than at any time in the past
2,000 years."

Horton's team also matched up the sediment core sea level record
with local and global tide gauge records. They also found that
their observations could be described using a model relating the
rate of sea-level rise to global temperature, similar to that used
by the science panel to calculate the one metre by 2100 projection.
All three methods showed good agreement, as you can see in the
graph below:

NC-20

But local development group NC-20 decided to take a stand against
these so-called projections. According to
Science magazine, the group "fears that planning and
retrofitting buildings and roads with a 1-meter rise in mind would
be a tremendous waste of money. 'You can't mandate [something] for
an entire region of the state based on hypothetical data," says
[NC-20 chair Tom] Thompson.'"

Instead, NC-20 wants scientists to forecast sea level rise by
extrapolating forward the linear increase in sea level over
time from one tide gauge in North Carolina, giving a sea level rise
of about 20 centimetres by 2100 - a fifth of that suggested by the
science panel.

This interesting approach attracted the attention of Comedy
Central's Stephen Colbert, who
points out in his segment on the bill that this is like
deciding that based on previous data, you won't die:

"I've been alive all my life. Therefore,
I always will be."

NC-20 has written a paper
setting out its opposition to the scientists' position. Most of the
experts it cites are too modest to be named, but one familiar name
is
Nils-Axel Mörner, who has a penchant for downplaying sea level
rise. Mörner's former colleagues ungallantly
distanced themselves from him earlier this year when he claimed
the Maldives are under no risk from flooding, based on an unusual,
if rather limited evidence base, including the shape of the islands
and the position of a woman's skeleton found in the area.

NC-20's stated aims include
furthering development through scientific research - which seems
difficult to square with a decision that runs counter to many years
of scientific research which, as Horton points out, "is rigorously
peer-reviewed, vetted, prior to ever being published and presented
to the public".

In its response to the science panel report NC-20 also disputes
the theory of global warming. We
quote:

"The bottom line here is that until we
can do all of the following, that coming up with a future sea level
rise prediction is nothing short of reading tea leaves:
1) scientifically prove AGW [anthropogenic global warming],
and
2) scientifically prove the exact effects of each of the numerous
other factors identified to influence sea-level rise, and
3) scientifically prove the additional AGW component, if any."

It's a refreshingly old-school position that even most climate
skeptics tend to shy away
from these days.

The bill's broader implications

Senate Minority Leader Martin Nesbitt, one of the 11 senators who
voted against the bill,
says:

"This bill has made us the laughingstock
of the country".

Although this may be right, it might also be short-sighted. As
Horton told us, the proposed bill has implications beyond North
Carolina's sea level over the coming century:

"The bill is the beginning to the end of using science in
developing policy for the State of NC. The proposed bill will
ultimately prevent the state from obtaining scientific facts when
developing future projections of sea level and coastal
vulnerability."

Professor David Vaughan, British Antarctic Survey, told us that
the accelerating sea level rise might be "difficult to spot" for
the residents of coastal communities:

"This is not about the sea chasing
people up the beach, it's really about a progressive change in the
frequency of flood events. Even on the mid-range projections,
towards the end of the century many coastal communities will see
flood events every decade that they previously suffered only once a
century".

Sounds expensive. Luckily, at least in North Carolina, that sort
of talk could soon be against the law.